A 100Hz HP is just at the resonance of the 881. I don't think a single cap will provide you the FR you need. You either need an active crossover or something more complicated than a single cap crossover. Another option could be a sealed box if it can offer the right HP i.e. at the same frequency of the subwoofer LP.
Ralf
I don't see the need to add a tweeter to a small 3" fullrange driver. IMHO the TB should be used with a FAST approach with a crossover at 300-400Hz.
Enough to filter out the low bass pump?
Only thing i want is make a boombox with high quality sound. I must say the tpa3116d2 with subwoofer and 2 881 are sound pretty awesome! The tweeter is not a must but filter the frequencys below 100hz is!
I had already search for diy 3 way crossover but it only give me 800hz and 8000hz or 600hz and 6000hz if you know what i mean?
Sorry I didn't mean to sound snotty. I am always surprised how good the TB-871 sounds. Yes none of this is super quality but it will be okay. But as ScottJoplin says a 1st order x-over , a single capacitor in line with the 881, will still deliver a lot of low frequency information to the 881. Try a second order or a first order (capacitor) at a higher frequency ... 150-200Hz. This calculator shows the value of the capacitor required. Ignore the inductor for the woofer. I run the 871 full range but it cannot go very loud.
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Oke i don't understand..why must i use 200hz highpass..and sorry i really try to understand but i don't get it about second and first order en capicitor and all that stuff.
Can i use this --> https://www.parts-express.com/100-hz-high-pass-8-ohm-crossover--266-462
A high pass crossover filter(capacitor) removes low frequency information which your 881 clearly cannot handle. Use an online crossover calculator like I showed you in the image in my last post. There are many such crossover calculators online. Just google. Or buy a cap as shown in the image I attached from PartsExpress. A non-polarized is cheapest. And read some basic information on speaker design. There are introductions to the topic online. There is no excuse with all the online resources to be asking such basic questions here. But we all started somewhere.
Yes the crossover you posted a link to is a good idea. It is a 2nd order. It uses two components that each shift the phase by 90 degrees so hence called a 2nd order. It cuts off the low frequencies more sharply than a first order capacitor only cross over.
Yes the crossover you posted a link to is a good idea. It is a 2nd order. It uses two components that each shift the phase by 90 degrees so hence called a 2nd order. It cuts off the low frequencies more sharply than a first order capacitor only cross over.
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How about this --> Crossover Networks for Loudspeakers
Use a highpass for the tweeter and a bandpass for the midrange
Use a highpass for the tweeter and a bandpass for the midrange
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Yeah a 1st order 200uF cap crossover does practically nothing as the frequency response of the driver falls off about equally anyway. Modelled it in XSim.
The whole point of a crossover is to increase the impedance in the frequency range where you want attenuation. The RLC as you say, Lojzek, gives a smooth system impedance curve and attenuates the FR more dramatically.
Again this RLC looks expensive!
DIY is not alway cheaper.
The whole point of a crossover is to increase the impedance in the frequency range where you want attenuation. The RLC as you say, Lojzek, gives a smooth system impedance curve and attenuates the FR more dramatically.
Again this RLC looks expensive!
DIY is not alway cheaper.
https://www.parts-express.com/80-hz-high-pass-8-ohm-crossover--266-458
And if i use only this (without tweeter)
I have all the parts for my boombox, the only thing is that with high bass music the speaker extends to much. So now i'm with the problem that i can't make my boombox ready because of the low bass. So the only thing i must do is block that frequencies, but because the speaker is 6.6 ohm i can't find a good crossover.
If i put a 220uf capacitor it is tuned at 110 hz wich is perfect, but you say it is expensive!!..?
Sorry for all the questions but it is really sad that i can go finish the project because of that low bass. Thank you very much😃
Official TB data of W3-881 sjf is suspicious to me in that it extends too much in the low bass and if you check TS parameters the cabinet related cut-off in 3 litre sealed box is significantly higher than what infinite baffle measurements suggest. This is a sim of the official FR graph with cabinet response spliced at 300 Hz. Baffle step was calculated as if the baffle measured 4" by 6", and the unit was in the centre of it, sharp edges.
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